Shailene Woodley and Sam Claflin fight for survival in Adrift, about a couple who sail into one of the worst hurricanes in recorded history. They tell Laura Harding about their bizarre first meeting

SHAILENE WOODLEY and Sam Claflin had actually once met before they made a movie together - it's just a shame she has no recollection of it. "Sam loves to point out that we met before and had a beautiful long conversation years and years ago that I don't remember," she laughs. "It's ok, I've forgiven you now," Claflin replies benevolently.

It's unlikely Woodley, 26, will ever forget him now, after the duo spent weeks together at sea making their new film Adrift. They star in the true-life story of couple Tami Oldham and Richard Sharp, who inadvertently sailed directly into one of the most catastrophic hurricanes in recorded history on a journey from Tahiti to San Diego. In the aftermath of the storm, Tami wakes up to find Richard badly injured and their boat in ruins, and she must find the strength to save them both.

"I was so captivated by it," the Big Little Lies star says, "by who Tami is and the love story. I really felt the energy of the divine soulmate connection between Tami and her fiance."

But her path to the role was not entirely a smooth one. She didn't immediately sign on for the film because she was under arrest for participating in a protest at the Dakota Access Pipeline when it was sent to her. "I got the script via email the day I was arrested and it got lost in my inbox. Then, a month later, my agents called me and asked me if I'd read it, and that's when I realised I had completely missed it!"

Having grown up on the water, the role felt perfect for the California native, but still pushed her to her limits.

"I grew up a lot on lakes, so am very comfortable in the water, but lakes are obviously very different than the ocean. When I was 18, I moved to Hawaii and so that was my introduction to the ocean, and it is just a different beast. You have to have a respect for the sea because you can go from having fun to being in a very dangerous situation within a matter of seconds. I think this movie just affirmed that respect and that constant awareness of watching the ocean and listening to the little message that tell you maybe it's time to vacate."

The first time British star Clafin, now 32, and Woodley met, they both taking part in a photoshoot. Woodley had just finished making The Descendants, her breakout film from 2011 in which she starred opposite George Clooney, while Claflin was in the middle of filming Catching Fire, the second of the Hunger Games movies.

"I had literally just broken my finger on the film set on the Friday," he recalls. "Then I had to fly to LA to do this photoshoot and they put me in a plaster cast. I had just watched The Descendants, so we were initially talking about that and I think that is how we initiated the conversation.

"It was a photoshoot with about 150 young actors, all the rising stars of whatever, and I remember we were in this house and there were loads of dead animals all over the wall and we were talking about how tacky it was. There was a baby giraffe that was stuffed in the corner of this room and elephants and we were just talking and that."

Somehow this still doesn't ring a bell for Woodley. "I haven't forgiven myself for forgetting," she says remorsefully. "Mostly because I'm jealous that you have a memory that I don't have."

Fortunately, they hit if off straight away when they rehearsed together for two weeks in Fiji before they started filming.

"We immediately felt a fondness for each other," Woodley says. "We really just clicked. It was great to get to know him outside the work environment, to go over the script and he is hands down, the hardest-working, most generous, compassionate, kind, loving, enthusiastic, beautiful individual that I have ever worked with, male or female.

"The elements that we were working in were not easy, shooting on a boat in open water for 14 hours. Never once did he complain. Never once did that man get tired. Not only is he incredibly professional, but so creative and so fun to be around."

Putting them through their gruelling paces was Icelandic director and keen outdoorsman Baltasar Kormakur, who is responsible for films such as Everest and The Deep. The team filmed for 49 days, most of it out on the open water in Fiji, and he was determined it would be as authentic as possible.

"I do feel there is a real value in actually experiencing these kind of true life, man vs. nature stories," he says. "Or in this case, woman vs. nature. I think that kind of authenticity translates for the audience and certainly helps everyone, cast and crew, relate to the story, the emotions.

"Being out on a boat in this vast ocean as the waves are hitting for 12 to 14 hours a day, you just can't fake it. It does give a sense of what it must have been like for Tami and Richard. Especially for the actors, it strips them down to the essentials. So I try to do as much as is safe in the elements."

A different kind of authenticity came when about midway through production, the real Tami visited the set.

"I was hyper-aware of how emotional this experience must be for her," Woodley says, "the trauma of being stuck out at sea. She's such a profound, strong individual who truly seemed to embrace this film. My prayer is that she has found healing as well through this experience."

For the real-life woman, it was a surreal but also gratifying time. "It was a dream come true, to see all the hard work and dedication and care everyone had. Their real dedication to telling my story.

"It was so wonderful when Shailene raised her hand and said she would do the film; she was just perfect and so thoughtful and generous of spirit to me. And then when Sam came aboard, he was just great. It's uncanny how much he looks like Richard and he had that charismatic way about him that Richard had. I think the universe sent us Sam to play Richard.

"When I came to set and saw Shailene and the wrecked Hazana boat, it was an out of body experience. It just hit my heart. The experience at the time made me understand that I had a wellspring of inner strength and a fortitude, a will to live that I hadn't recognised before. But seeing everything again also underscored how lucky I really was to survive."

  • Adrift is out in UK cinemas now.